Rotary piston engine, pump or other machine



H. SCH UDT 3,398,643

ROTARY PISTON ENGINE, PUMP OR OTHER MACHINE Aug. 27, 1968 3 Sheets-Sheet1 Filed June 27, 1966 INVENTOR HANS SC/QY/DT B'Y g i A TTOR/VE Y H. SCHUDT 3,398,643

ROTARY PISTON ENGINE, PUMP OR OTHER MACHINE Aug.'27, 1968 3 Sheets-Sheet2 Filed June 27, 1966 A IOAIVEV H. SCHUDT Aug. 27, 1968 ROTARY PISTONENGINE, PUMP OR OTHER MACHINE s Sheets+$heet I Filed June 27, 1966 7 pL, W C .P m ms If N v M A 8 Y 5 M 6 a n 6 5 G 6 W u 7/ w w a 0 n 7 u n Ga a J United States Patent 3,398,643 ROTARY PISTON ENGINE, PUMP 0R 1OTHER MACHINE Hans Schudt, 64/66 Darmstadter Str., 6079 Sprendlingen,Hesse, Germany Filed June 27, 1966, Ser. No. 560,665 Claims priority,application Germany Iuly 30, 1965, Sch 37,473 1 Claim. (Cl. 91-60)ABSTRACT OF THE DISCLOSURE An opposed piston rotary engine or pumpembodying four oval gears controlling the opposed pistons throughtwo-to-one gearing, and a power shaft driven by the two oval gearsplaced in the gear train most remote from the pistons.

The invention herein disclosed is a rotary piston machine adapted tooperate as a power source or as a work producer.

In the first category, the invention may be embodied, for example, inthe form of a steam engine, compressed air or hydraulic engine and inthe second class the invention may be incorporated in various pumpstructures for handling different kinds of liquids and gases.

The objects of the invention generally have been to provide a simple,substantial, compact machine having few, smoothly operating parts,controlled effectively to accomplish the desired cycles of operation.

Special objects of the invention have been to utilize full displacementpossibilities and gain maximum efiiciency in a compact machine structureand to avoid sealing difliculties such as sometimes encountered inrotary machines.

Briefly the invention may be considered as embodying a casing having acircular chamber with walls defining an annular working channel ofconstant cross section and provided with at least one inlet and oneoutlet, shafts journaled on the axis of said chamber, opposing pistonscarried by said shafts, conforming to the cross section of said annularchannel and gearing connected with said shafts for effecting approachand separation of the pistons to vary the contained volume between thepistons at predetermined definite stages in rotation of the pistons inthe chamber and in respect to the inlet and outlet of the casing.

Other novel features of the invention and desirable objects accomplishedare set forth or will appear in the course of the followingspecification.

The drawings accompanying and forming part of the specificationillustrate certain present practical embodiments of the invention.Structure and operation, however, may be modified and changed as regardsthe immediate disclosure, all within the true intent and scope of theinvention, as hereinafter defined and claimed.

FIG. 1 is a perspective view of the pistons for a two piston machine andwith the shafts carrying the pistons arranged to extend out one side ofthe machine housing, the latter not shown.

FIG. 2 is a similar view showing how the shafts carrying the pistons maybe arranged to extend out opposite sides of the casing, the latter notshown.

FIG. 3 is a longitudinal sectional view of a pump with the pistons ofFIG. 1 incorporated therein and eccentric oval gearing provided foroperating the pistons in desired relation, this view being taken onsubstantially the plane of line 3-3 of FIG. 4.

FIG. 4 is a cross sectional view as on substantially line 4-4 of FIG. 3.

3,398,643 Patented Aug. 27, 1968 FIGS. 5 and 6 are similar crosssectional views illustrating successive phases of movement of thesynchronized opposed pistons.

FIG. 7 is a perspective view of a four piston embodiment of theinvention with diametrically opposite pistons connected in pairs.

FIG. 8 is a broken longitudinal sectional view of a rotary piston engineembodiment of the invention with pistons controlled by differentialgearing, this view taken on substantially the plane of line 8-8 of FIG.9.

FIG. 9 is a cross sectional view on substantially the plane of line 9-9of FIG. 8.

FIGS. 10 and 11 are cross sectional views illustrating successive phasesof movement of the pistons.

FIG. 12 is a perspective view of a four piston engine arrangementcontrolled by oval gearing.

FIG. 13 is a longitudinal sectional view of the component parts of suchan engine.

FIG. 1 illustrates the basic concept, of two pistons 1, 1 shaped to fitthe annular working channel of a circular casing, on part circular hubs3, 4 in end-to-end relation, forming the inner circular wall of theannular channel and mounted on shafts 5 and 6, rotating on a common axis2.

In this view, both shafts project in the same direction and so may beextended out through one side of the housing.

The construction shown in FIG. 2 differs from the first in that theshaft supported lobes 1, I extend in opposite directions and so mayproject through opposite sides of the housing.

FIGS. 3 to 6 illustrate the invention developed as a pump, with thepistons operating in a circular cylindrical housing 9, provided with acover 10, with the walls of the circular chambered housing, cover andhubs forming an annular channel 11 in which the pistons rotate.

A tubular extension 9' on the back of the housing provides a beamingsupport for the shafts 5 and 6.

The free ends 5' and 6' of the shafts extend out of the housing and areconnected with separate outputs of a transmission gearing, designated asa whole as 12, FIG. 3.

By this transmission, the pistons are positively controlled in theirrotary movement in the annular channel in the direction of arrow 13,FIG. 4, to effect approach at a predetermined point 14, FIG. 5, so thatupon each full revolution, the piston shown at the left will reach aminimum distance from the piston moving in front of it and at the sametime provide maximum distance between the 0pposite faces of the pistonsat position 15, diametrically opposite the point 14.

In FIG. 5, the piston at the left has reached the point of closestrelation to the piston at the right, which may be practically in contactand piston at the right has is forward surface at a point 15, thefurthest separation from the piston in front of it, the left piston.

Symmetrically related to the point 14 of the annular channel 11, thehousing 9 is provided with an inlet 16, and an outlet 17.

The transmission gearing 12 includes a drive shaft 18, FIG. 3, carryingoval gears 19, 20, displaced apart and in mesh respectively withcorresponding oval gears 21 and 22 on shafts 6 and 5 carrying thepistons.

The gears 21 and 22 are fixed on shafts 6 and 5, in position to effectthe relative approach and separation of the rotating pistons asdescribed, the shafts of these gears each representing a gearing outputfor such purposes.

The pistons in the present dislosure are slidingly guided on the wallsof the housing by surface contact and the angular or circumferentialextension of these pistons as shown provides efficient surface seal withthe walls of the annular channel.

For practical purposes, the pistons may be of plastic having goodsliding characteristics.

In FIG. 4, the working space 23 between the front of the upper pistonand the back of the lower piston is in communication with the inlet 16,and at the same time, the working space 24 between the front of thelower piston and the back of the upper piston is in communication withthe outlet 17.

The oval gears are placed to cause each piston to move faster in thelower region of its rotation than in the upper region, so that in theillustration, the right hand working space 23 is increased upon furthermovement, while the left hand working space 24 is rapidly reduced insize.

Therefore, the fluid worked in the pump is drawn in through inlet 16,while fluid already taken in is pressurized or compressed and ejectedthrough outlet 17 In FIG. 5, the circumferentially extended portion ofthe piston at the right has closed the inlet 16, while the other pistonhas closed outlet 17.

The pistons in this position have reached the point of minimumseparation or maximum approach, with fluid drawn into the working space23, then at a maximum, contained in the lower portion of the annularchannel, here shown as shut off from both inlet and outlet.

On further movement to the FIG. 6 position, the working space 23 iscarried into communication with outlet 17 and the working space 24 isopen to inlet 16. Thus fluid in space 23 is compressed or subjected topressure and discharged through outlet 17, while fresh fluid is beingtaken in through inlet 16.

The exact operation of the pump enables it to be used as a dosaging pumpin packaging processes and is suited for use for circulating or manyother purposes.

In the four piston machine illustrated in FIG. 7, there are twodiametrically opposite pistons 25, and a second pair of diametricallyopposite pistons 26, on part circular hubs 27, and 28, fixed onconcentric shafts 29 and 30 respectively.

The inner shaft 29 is shown controlled by an irreversible clutch 31,permitting rotation in only one irection and similarly the outer,tubular shaft 30 is shown controlled by a non-reverse clutch 31,permitting rotation in only the one direction.

The shafts 29 and 30 are connected with separate outputs of thetransmission gearing 32, controlling the piston movement as abovedescribed.

The transmission 32, FIG. 7, may be the oval gearing illustrated ordifferential gearing or a hydraulic transmission.

The internal combustion engine form of the invention shown in FIGS. 8 to11 embodies the paired piston structure illustrated in FIG. 7, with onefixed pair of diametrically opposite pistons 25, 25 opposed to similardiametrically opposite pistons 26, 26, operating in a circularcylindrical housing 33, with cover 34 providing an annular channel 35.

The housing has tubular bearing extension 33 for the piston shafts 29,30, and these shafts are shown connected with separate outputs of adifferential gearing 36, FIG. 8, controlling the piston movement.

Shafts 29 and 30 are shown connected with reverse checks 37 and 38,which may be in the nature of bicycle coaster brakes and permittingrotation in only one direction.

The differential gearing 36 may be similar to an automotive differentialwith bevel gears 39 and 40 on shafts 29 and 30 in mesh with planetarygears 41, on a spur gear 42, in mesh with a pinion 43, on a drive shaft44.

In the rotary piston machine of FIGS. 8 to 11, the rotary motion of thepistons is controlled so that each full revolution is divided into twosections of equal size or volume and each piston during each half ofrevolution, at given points 45 and 46, FIG. 9, approaches the minimumdistance from the piston preceding it and moves away during each halfrevolution at predetermined positions 47 and 48 to maximum distance awayfrom the preceding piston.

By the two pairs of pistons 25 and 26, four working spaces 49, 50, 51and 52 are defined in the annular channel 35.

Upon each complete revolution, the volume of each of these four workingspaces is reduced twice to a minimum and increased twice to a maximum.Accordingly, in each of the working spaces 49, 50, 51, 52, upon acomplete revolution of the pistons, a complete fourstroke cycle iseffected, the housing having suitable inlet 53 and outlet 54 at thebottom.

At the top, the housing 33 is shown as enlarged at 55, into a chamberfor a spark plug 56, fuel injection nozzle or the like.

FIG. 9 shows the working space 51, between the lower opposed pistons incommunication with inlet 53, and the working space 49 at the top incommunication with the recess 55.

With direction of rotation in the sense of arrows 57, the movement ofthe pistons is controlled so that they movemore slowly in the upper andlower regions of the annular channel 35, and more rapidly in the lateralregions.

In FIG. 9, the compressed combustible mixture in working space 49 isignited by spark plug 56, forcing these pistons apart with movementcontrolled by differential gearing 36, in combination with nonreversechecks 37 and 38, effecting forward rotation.

At this same time, the diametrically opposite working space 51 isincreased in size to draw fresh fuel mixture in through the inlet 53.

In the working space 52, the mixture is compressed and spent gases inworking space 50 are discharged through outlet 54.

Thus as shown in FIGS. 9, 10 and 11, a suction stroke is being effectedin working space 51, compression in space 52, expansion with performanceof work after ignition in working space 49, and exhaust of gases inspace 50.

During a complete revolution of the pistons, there takes place once ineach working space 49, 50, 51, 52, each of the four working strokes,suction, compression, expansion and exhaust.

The differential gearing 36 transmits the energy developed to the drivenshaft 44.

The construction illustrated in FIGS. 12 and 13 is generally similar tothat last described, except that the oval gearing designated 58 isemployed instead of differential gearing.

The piston shafts 29 and 30 are shown as carrying like gears 59 and 60,in mesh with pinions 61, and 62, forming step-up gearing.

Pinion 61 is connected with an oval gear 63, by a shaft 64, and pinion62 is connected with a reversely disposed oval gear 65 by aconcentrically journalled shaft 66.

Oval gear 63 meshes with a reversely disposed oval gear 67 and oval gear65 meshes with a reversely disposed oval gear 68.

Both the final oval gears 67 and 68 are fixed apart on a common drivenpower shaft 69.

This machine operates in the same manner as described in respect toFIGS. 9, 10 and 11, but with the advantage however, that it may bedeveloped either as an engine or as a working machine. In the lattercase, the shaft 69 would be driven by a motor and instead of the placefor the spark plug, there would be provided usually an outlet and aninlet, so that upon a full revoluton of the pistons, two operatingcycles would be created with the machine operating for instance, as acompressor.

The invention is not limited to the examples given. Depending on thepurpose of use and on operating speed, the seal between the pistons andwalls of the annular channel may be provided by close engagement of thecompanion surfaces or surface packing may be provided and in some cases,a slight clearance may be provided between opposing surfaces, leaving aslit seal and pistons rotating without contact, the slits being soslight that equalization of pressure between working spaces will nottake place. Also spring loaded pressure seals may be used. The annularchannel may be developed in the form of a torus and have a circularcross-section with correspondingly circular rotary pistons. In thelatter case, piston rings may be used to assure proper seal.

Rotary piston machines embodying the invention may be developed ascompressors or internal combustion engines of Diesel or spark plug type,or as steam or compressed air engines.

The simple circular shape of the working chamber and the simple rotarymovement of the pistons provide smooth operation, effective sealing andlow cost manufacture, operation and servicing.

Provision for heating or cooling, if found desirable, may be readilyapplied to the circular casing of the machine and sealing andlubrication of the control gearing may be efiected by enclosing the samein a casing connected or associated with the main housing.

The angular, arcuate extent of the pistons may be varied to suit theaction and purposes of the machine and to utilize the maximumdisplacement which the invention provides.

The machine is adapted for low or high speed operation and the differentforms of transmission gearing may be used as best suited to suchoperation. The eccentric, oval or elliptical form of gearing may bepreferred for many purposes because of simplicity and study character.

In the engine form of the invention illustrated, the power impulsecreated between adjoining pistons at the moment of near or closestapproach imparts forward motion to the leading piston, while thefollowing piston is slowing to an approach to rest, while supported bythe compression force exerted on the back of it.

What is claimed is:

1. A rotary piston machine comprising the combination of a housinghaving a cylindrical working chamber,

concentric shafts journalled centrally in said chamber,

a pair of diametrically opposite pistons on each of said shafts, bothpistons of the'two pairs in alternating order and in cooperativerelation with the walls of said cylindrical chamber, with the pistons oneach shaft in opposed relation to the pistons on the other shaft,

concentric countershafts journalled parallel to said concentric pistoncarrying shafts,

a power shaft journalled parallel to said countershafts,

two to one gearing between said concentric countershafts and saidconcentric piston carrying shafts for maintaining two to one ratio ofrotation of said countershafts and piston carrying shafts,

oval gears fixed in diametrically opposite extended balanced relation onsaid power shaft,

corresponding oval gears on said countershafts in mesh with said gearson the power shaft with maximum and minimum radiants of the same phasedto effect approach and separation of leading and following pistons twiceto each revolution of the same in said cylindrical chamber, and

said chamber having an intake port controlled by said pistons andpositioned at a point in line with the separating movement of a pair ofleading and following pistons and an exhaust port controlled by saidpistons at a point in line with a position of approaching movement ofleading and following pistons.

References Cited FOREIGN PATENTS 1,275,423 10/1961 France.

RALPH D. BLAKESLEE, Prmary Examiner.

